xii COMPARATIVE ANATOMY 



B. Special 



1. Amphineuka 



2. c4a.ste0p0da 



3. soaphopoda 



4. Lamellibeanchia 



PAGE 



201 

 201 

 201 

 206 

 206 



5. Cephalopoda ■ 208 



XVIII. The Body Cavity 211 



XIX. The Nepheidia 215 



A. Amphineuka 216 



B. Ga.stkopoda , 217 



C. Scaphopoda 221 



D. Lamellibeanchia . 221 



E. Cephalopoda 222 



XX. Genital Oegass 225 



A. Genekal 225 



B. Special . 227 



XXI. PARA.S1TIC Gasteopoda . 244 



XXII. Attached Gasteopoda 248 



XXIII. Ontogeny . 248 



A. Amphineuea 248 



B. Gasteopoda 252 



XXIV. Phylogeny . 268 



R'jvi'no of the most Iniportmit Literniv rr 269 



Appendage, — Rhodope Vekanii 281 



CHAPTER VIII 



ECHINODERMATA 



Systematic Review . . 285 



Class I. Holothurioidea 285 



II. ECHINOIDEA . 288 



III. ASTEEOIDEA . 295 



IV. Ophiueoidea 299 

 V. Pelmatozoa . 302 



1. Crinoidea 302 



2. Cystidea 313 



3. Blastoidea . 314 



I. General Moephology of the Echinodeem Body 315 



II. Moephology of the Skeletal System . 317 



